Some of the world's biggest banks have pushed back against bitcoin, warning of "potential risks" just as futures trading in the digital currency is due to begin.
The Futures Industry Association, whose members include the major Wall Street and UK banks, warned of a lack of transparency over how the contracts would be regulated, as well as the unpredictability of the underlying cryptocurrency, the Daily Telegraph reported
"We remain apprehensive with the lack of transparency and regulation of the underlying reference products on which these futures contracts are based," the FIA said in an open letter to the Commodity Futures Trading Commission, the US market regulator.
It added that it was unsure "whether exchanges have the proper oversight to ensure the reference products are not susceptible to manipulation, fraud, and operational risk".
The Chicago Board Options Exchange (CBOE) tomorrow will launch the first bitcoin futures market, in what is seen as a landmark moment that will help usher in the cryptocurrency's mainstream acceptance. The CBOE and Chicago Mercantile Exchange, which will launch a week later, have both won approval from the CFTC to operate under a self-certified regime.
The FIA said that the inherent riskiness associated with cryptocurrencies made this irresponsible.
The intervention from the FIA, whose members are responsible for clearing futures trades, appears to dash suggestions that bitcoin is gaining legitimacy.
"The launching of these innovative products through the 1-day self-certification process did not allow for proper public transparency and input," it said.
"This process does not distinguish for a product's risk profile or unique nature. We believe that this expedited self-certification process for these novel products does not align with the potential risks that underlie their trading and should be reviewed."
It came despite Jamie Dimon, the chief executive of JP Morgan and one of the most vocal Bitcoin critics of late, appearing to soften his criticism of cryptocurrencies.
"I'm open-minded to uses of cryptocurrencies if properly controlled and regulated," he told CNBC.
Bitcoin's price is at about US$15,644 ($22,880), down from the $17,000 highs of Friday.